1. Field of Invention
The present invention relates to a composite substrate and a method for manufacturing the composite substrate.
2. Description of the Related Art
Acoustic wave devices manufactured by arranging electrodes on a composite substrate including a support substrate and a piezoelectric substrate that are bonded together have been known. The acoustic wave devices are used as, for example, band-pass filters in communication devices, such as mobile phones. Patent Document 1, for example, discloses a composite substrate including a piezoelectric substrate formed of lithium niobate, lithium tantalate, or the like and a support substrate formed of silicon, quartz, or the like. According to Patent Document 1, the piezoelectric substrate and the support substrate are bonded together by applying an ultraviolet-curable adhesive to the support substrate by spin coating.